Take-up device for circular knitting machine



TAKE-UP DEVICE FOR CIRCULAR KNITTING MACHINE Filed Sept. 15, 1955 July 9, 1963 T. 1.. CAPES ETAL 2 Sheets-Sheet 1 FIG.1

INVENTORS T. L. CAPE S G. G. NORMAN ATTORNEY July 9, 1963 CAPES ETAL 3,096,634

TAKE-UP DEVICE FOR CIRCULAR KNITTING MACHINE Filed Sept. 15, 1955 2 Sheets-Sheet 2 INVENTORS T. L.CAPES G. G. NORMAN ATTORNEY United States Patent Office 3,096,634 Patented July 9, 1963 3,096,634 TAKE-UP DEVICE FOR CIRCULAR KNITTING MACHINE Tasker L. Capes and George G. Norman, Moreland, Ga., assignors to Hemphill Company, Hopedale, Mass., a corporation of Massachusetts Filed Sept. 13, 1955, Ser. No. 533,956 Claims. (Cl. 66-150) This invention relates to the art of manufacturing knitted fabrics and more particularly to methods and machines used to produce stockings, particularly those of a fine gauge.

This invention specifically relates to an automatic takeup mechanism for use with circular knitting machines particularly of the type on which individual stockings may be knit starting with :bare needles, such as the machine disclosed in the patent to R. W. Scott, No. 1,282,- 958, dated October 29, 1918.

Heretofore, the mere weight of the stocking has been used to withdraw it downwardly from the needles or various takeup devices such as extra weights have been used to apply tension during knitting. Such take-up devices often produced stockings having streaks or having knit-in of the ends of the yarn changes, as well as other irregularities. Also, the prior take-up devices sometimes exerted too high a tension on the stocking resulting in needle breakage, thereby necessitating the stopping of the machine to repair the damage, the loss of time adding to the cost of producing the stockings.

It has been recognized in the past that stockings having streaks or those having knit-in of the ends of the yarn changes and other irregularities resulted from improper tension on the stockings during withdrawal from the needles. Also, if the tension is not maintained uniform there are likely to be produced shadow areas with streaks or regions having the appearance of being scratched. In an effort to apply uniform tension to the stocking during its production a connection was provided between successive stockings and take-up rolls were used, the tension being applied through the take-up roll to the stocking, each stocking in turn passing through the pick-up roll. After the stocking was withdrawn from the machine the connection was then severed from the stocking and further operations were necessary to complete the stocking. Although this method of manufacturing stockings was an improvement, it required additional operations after discharge from the machine. It is an object of the present invention to provide a take-up mechanism for a circular knitting machine that will result in overcoming the above enumerated difi'iculties and consequently will result in the production of a higher percentage of first quality stockings and more economical operation of the machine thereby permitting production of better stockings inexpensively.

Another object of the present invention is to provide an automatic take-up device which will eliminate the streaks in sheer hosiery, provide proper and uniform tension during the knitting period, and produce a smooth fabric throughout the entire stocking.

Another object is to provide a take-up device which can be readily attached to existing machines and operated automatically therefrom.

A further object is to provide a take-up device for circular knitting machines which will automatically release the material upon its completion and eject it from the knitting machine into a receiver.

Another object is to provide an automatic take-up device that will provide a uniform tension along the length of the stocking thereby eliminating the twisting of the welt of the stocking within the cylinder of the machine during its production.

Other objects and advantages of the invention will be apparent from the following description taken in conjunction with the accompanying drawing wherein:

FIGURE 1 is a perspective of the lower portion of a circular knitting machine showing the present invention attached and in position to apply uniform downward tension to the knit material;

FIGURE 2, a side elevation of the .applicants take-up device and showing a portion of the circular knitting machine in phantom lines;

FIGURE 3, a front elevation of the device;

FIGURE 4, a fragmentary side elevation to an enlarged scale of a portion of the tube and the rotatable sleeve of applicants invention; and

FIGURE 5, a section on the line 44 of FIG. 4.

Briefly stated the invention comprises a vacuum take-up mechanism for use with a circular knittting machine of the type on which individual and separate stockings are knit starting with bare needles. The take-up mechanism consists of a tube attached at the lower end of a cylinder of a circular knitting machine, and a vacuum source connected to the lower end of the tube by a valved conduit, the tube having a perforated disk therein to prevent stockings from being drawn past it into the conduit. A concentric sleeve is rotatably threaded around the outside of the tube, the sleeve having an .aperture which may be placed in registration with an aperture in the side wall of the tube, the aperture in the sleeve communicating with a stock-ing receiver for temporary storage of the stockings as they are discharged from the tube. Linkage is connected to the sleeve and actuated by a cam on the knitting machine for rotating the sleeve to bring the apertures into or out of registration.

The source of vacuum is also connected to the stocking receiver by a second conduit. Valve means in the conduit may be positioned to connect the vacuum to the tube while the apertures are out of registration, to provide take-up, or to the receiver while the apertures are in registration to draw the material into the receiver. The valve means is operated from a cam on the knitting machine.

With reference to FIG. 1, the lower portion of a conventional circular knitting machine 10 is disclosed having legs 11 supported above the floor by platform 12. The knitting machine 10 is provided with a cam drum 13 and a lower discharge cylinder 14 through which 'material such as a stocking extends as it is knitted. The cam drum has a series of cam lobes on it adapted to control various portions of the knitting machine during the knitting process. All of the foregoing structure is conventional and well known.

A tubular chamber 15' is attached at its upper end to the lower end of the cylinder 14 of the knitting machine. At the lower end of the tube 15 a flexible conduit 16 is connected to a source of vacuum 17. The vacuum source 17 could be a vacuum line or a blower type fan as disclosed in FIG. 1.

A concentric sleeve 18 is rotatably mounted about the outer wallsof the lower end of the tubular chamber 15. A horizontal pipe or conduit sect-ion 19 is joined at one end to sleeve 18 and at the opposite end to a vertical conduit or pipe 20 which in tum communicates with a stocking receiver 21 for [holding the stockings as they are ejected from the tubular chamber 15. The upper end of the pipe 20 extends into and terminates above the floor of the receiver 21. The receiver 21 has an access lid 22 permitting the ready removal of stockings therefrom during the course of production. The lid 22 can be frictionally held on the receiver 2 1 or it can be hinged at one side with a latch to fasten the opposite side.

A second vacuum or suction conduit 23 is attached 'between the vacuum source 17 and a side wall of the stocking receiver 21 for applying a vacuum to the receiver in order to withdraw the completed stockings from the tubular chamber into the receiver.

As shown in FIGS. 1 and 4, the sleeve 18 has a lateral slot 24 into which a pin 25 extends, the pin 25 being integral with the tubular chamber 15. This structure is provided to properly anchor the sleeve 18 on the tube 15 with respect to its elevation during its rotational movement and to limit the extent of the rotational movement of the sleeve 18.

With reference to FIG. 5, air-flow means comprising a perforated disk 26 is mounted within the lower end of the tubular chamber 15 in order to keep stockings from being drawn into [the vacuum conduit 16 after release from the needles of the knitting machine. As shown in dotted lines in FIGS. 2 and 3, a second perforated disk 27 is mounted within the opening between the receiver 21 and the vacuum conduit 23 for preventing stockings within the receiver from being drawn into the vacuum conduit 23.

As disclosed in FIGS. 4 and 5 the lower end of the tubular chamber 15 has an opening 28 adapted to be placed in registration with a second opening 29 in the side wall of the sleeve 18. The opening 29 communicates with the horizontal conduit section 19. The openings 28 and 29 are positioned so that they are in registration when the receiver 21 is rotated forwardly of the machine to a position as shown in dotted lines in FIG. 2. When in this position stockings can enter the horizontal conduit 19 and be drawn into the receiver 21.

The sleeve 18 is further provided with a bracket 30 connected about its upper end and having an arm 31 which is connected to a linkage means for controlling the rotation of the sleeve 18 about the tubular chamber 15.

With reference to FIG. 2, a flap valve 32 is provided adjacent the connections of the conduits 16 and 23 to the vacuum source 17. This valve is operated by a crank 33 for either allowing the vacuum to be impressed on the conduit 23 or on the conduit 16, the valve sealing the vacuum from one conduit .as the vacuum enters the other conduit. The crank handle 33 is joined to a rod 34 which in turn is joined to a lever 35 which is pivoted on' a bracket 36 extending from the machine 10. The opposite end of the pivoted lever 35 has a follower 37 riding against a cam 38 positioned on the cam drum 13 of the machine 10. The cam 38 has a depressed portion into which the follower is adapted to drop at the proper moment, thereby actuating the lever 35 and operating the flap valve 32 to seal the vacuum from the conduit 16 and to allow the vacuum to enter the conduit 23. A tension spring 39 is attached to the outer end of the crank 33 in order to force the follower 37 against the cam 38.

The linkage rotating the sleeve 18 about the tubular chamber 15 comprises a rod 40 connected at one end to the arm 31 of the bracket 30 with its opposite end connected to the lower end of a lever 41 also pivoted on the bracket 36 extending from the machine 10. The upper end of the lever 41 has a follower 42 adapted to ride against a second cam 43 as shown in dotted lines in FIG. 2. A second tension spring 44 is connected to the lower end of the lever 41 to force the follower 42 against the cam 43.

Operation of the Take-Up As material is knit on the bare needles of the machine in a conventional manner, the flap valve 32 is operated by the cam drum 13 to seal the conduit 23 and to allow the vacuum source 17 to lower the pressure within conduit 16 thereby lowering the pressure within the tubular chamber 15-. This creates a substantial flow of air downwardly through the top of the machine 10 past the needles and through the cylinder 14 creating a force tending to withdraw the fabric downwardly as it is being knit. This force is uniform throughout the fabrics surface on both its inside and outside. It can be seen that such a force is ideal for creating a high quality stocking. This vacuum or suction is continued, in the case of hosiery, until the foot of the stocking is completed and the stocking is released from the needles of the machine, the stockings completion being controlled by the movement of the cam drum 13 of the machine 10. As this force is uniform, the welt of the stocking does not tend to twist within the cylinder 14 as the remainder of the stocking is completed.

After the stocking is released from the needles the earns 38 and 43 are so positioned to operate the flap valve 32 to seal the conduit 16 and to impress a vacuum on the conduit 23. At the same time the sleeve 18 and the associated receiver 21 are rotated to align the openings 28 and 29 of the respective tubular chamber 15 and the sleeve 18. The vacuum in the conduit 23 draws the stocking outwardly from the tubular chamber 15 and upwardly into the receiver 21.

After the stocking is drawn into the receiver, the cam drum 13 actuates the sleeve 18 through its associated linkage to again disalign the openings 28 and 29. At the same time the flap valve 32 is operated to seal the conduit 23 and to impress the vacuum on the conduit 16 for allowing the take-up device to apply tension to a new stocking as it is produced within the machine 10.

While a particular method has been described for moving the stocking from the tubular chamber 15 into the receiver 21, it is obvious that various other well-known means could be used to perform this function.

It will be obvious to those skilled in the art that various changes may be made in the invention without departing from the spirit and scope thereof and therefore the invention is not limited by that which is illustrated in the drawings and described in the specification, but only as indicated in the accompanying claims.

What is claimed is:

=1. A take-up mechanism for use with a circular knitting machine comprising an elongated tube adapted for attachment to the lower end of a cylinder of a circular knitting machine, said tube being provided at its lower end with a perforated disk, a vacuum source, said vacuum source being connected to the bottom end of said tube, a valve positioned between said tube and said vacuum source adapted to 'allow the vacuum source to act on said tube in one position and to seal the suction from said tube in another position, said tube having an opening along its side wall providing for the removal of a knitted article, a concentric sleeve closely fitting around the outside of said tube, said sleeve having an opening adapted in one position to be aligned with said opening in said tube, an article receiver for holding the knitted articles as they are removed from said tube, said receiver being connected to the opening in said sleeve by a conduit, said sleeve being adapted to rotate around said tube to either align or disalign the openings in said tube, linkage means adapted to be actuated from the cam drum on said circular knitting machine to automatically rotate said sleeve around said tube to align said opening when the article is to be removed from said tube, further linkage means for operating said valve to seal the vacuum source from said tube during the period of removal of the article from said tube, said further linkage means being adapted for actuation from the cam drum on said circular knitting machine.

2. A take-up mechanism 'for use with a circular knitting machine comprising an elongated tube adapted for attachment to the lower end of a cylinder of a circular knitting machine, said tube being provided at its lower end with a perforated disk, a vacuum source, said vacuum source being connected to the bottom end of said tube, a valve positioned between said tube and said vacuum source adapted to allow the vacuum source to act on said tube in one position and to seal the suction from said tube in another position, said tube having an opening along its side wall providing for the removal of a knitted article, a concentric sleeve closely fitting around the outside of said tube, said sleeve having an opening adapted in one position to be aligned with said opening in said tube, an article receiver for holding the knitted articles as they are removed from said tube, said receiver being connected to the opening in said sleeve by a conduit, said sleeve being adapted to-rotate around said tube to either align or disalign the openings in said tube, linkage means adapted to be actuated from the cam drum on said circular knitting machine to automatically rotate said sleeve around said tube to align said opening when the article is to be removed from said tube, further linkage means for operating said valve to seal the vacuum source from said tube during the period of removal of the article from said tube, said further linkage means being adapted for actuation from the cam drum on said circular knitting machine, said vacuum source being connected to said receiver by a pipe and exerting a suction within said receiver for removing the article from said tube.

3. In a circular knitting machine having a circle of needles and a take-up mechanism for the fabric formed thereon, said take-up mechanism comprising a tubular chamber projecting below said circle of needles, said chamber having air-flow means permitting the passage of air but preventing the passage of a knit article therethrough, a vacuum source, means attaching the vacuum source to said chamber for drawing air through said .airflow means, said chamber having a fabric discharge opening, valve means for alternately opening and closing said discharge opening, means connecting said vacuum source to said discharge opening, said valve means in one position permitting said vacuum to draw .air through said airflow means and in another position permitting said vacuum to draw air through said discharge opening, said valve means being connected to said machine, said machine automatically controlling the position of said valve means.

4. In a circular knitting machine having a circle of needles and take-up mechanism for the fabric formed thereon, said take-up mechanism comprising a tubular member extending axially of said circle of needles and defining a vertically positioned chamber for initially receiving fabric formed on said circle of needles, a first means including means in communication with said chamber at a first position for creating a flow of air through said chamber to tension said fabric during the formation thereof; and a second means including means in -communication with said chamber at a second position for creating a how of air to remove said fabric from said chamber.

5. In a circular knitting machine as defined in claim 4 wherein said first and second means includes a common suction means and there is a valve means for alternatively connecting said suction means to said first and second means.

References Cited in the file of this patent UNITED STATES PATENTS 2,275,276 Williams Mar. 3, 1942 2,636,364 Moss Apr. 28, 1953 2,694,304 Butler Nov. 16, 1954 2,709,352 Lawson May 31, 1955 2,729,082 Tew Jan. 3, 1956 

3. IN A CIRCULAR KNITTING MACHINE HAVING A CIRCLE OF NEEDLES AND A TAKE-UP MECHANISM FOR THE FABRIC FORMED THEREON, SAID TAKE-UP MECHANISM COMPRISING A TUBULAR CHAMBER PROJECTING BELOW SAID CIRCLE OF NEEDLES, SAID CHAMBER HAVING AIR-FLOW MEANS PERMITTING THE PASSAGE OF AIR BUT PREVENTING THE PASSAGE OF A KNIT ARTICLE THERETHROUGH, A VACUUM SOURCE, MEANS ATTACHING THE VACUUM SOURCE TO SAID CHAMBER FOR DRAWING AIR THROUGH SAID AIRFLOW MEANS, SAID CHAMBER HAVING A FABRIC DISCHARGE OPENING, VALVE MEANS FOR ALTERNATELY OPENING AND CLOSING SAID DISCHARGE OPENING, MEANS CONNECTING SAID VACUUM SOURCE TO SAID DISCHARGE OPENING, SAID VALVE MEANS IN ONE POSITION PERMITTING SAID VACUUM TO DRAW AIR THROUGH SAID VACUUM FLOW MEANS AND IN ANOTHER POSITION PERMITTING SAID VACUUM 